It’s not automatic, but you can technically block countries. From the Connections tab in Options, there is an IP Filter option for data files. I believe the format is X.X.X.X-Y.Y.Y.Y
Country IP assignments are handled by ARIN in North America and RIPE NCC for Europe. Those are the two main ones, but LATAM, Africa, and APAC territories have their own respective groups as well. So, every main German IP block is known and searchable via RIPE. You would have to format your lists using that info.
It may not be super effective as IPs can somewhat float, but that would be the method.